The caretaker of two pit bulls believed responsible for an attack on four pet llamas at a Ukiah-area ranch last week said Tuesday he believes the dogs have been mistakenly condemned for blood spilled by coyotes or some other predator.

Richard Bier, whose rescue dog, Cocoa, was shot dead during the incident, said the 4-year-old pit bull feared noise and violence and could not have participated in the attack that killed two llamas and maimed a third.

But authorities say deputies called to the Robinson Creek Road property where the llamas were savaged late Thursday night saw the dogs repeatedly circle back toward the surviving livestock and display aggression toward the human officers.

The dogs represented a threat to public safety, the Mendocino County Sheriff's Office said. After repeated attempts to subdue them failed, one was shot and killed, authorities said.

The second dog, whom Bier said had been left in his care by a friend, is in 10-day quarantine to determine if it could have passed rabies to the injured llama, who survived the attack.

That dog will then be put down, Capt. Kurt Smallcomb said.

Bier also has been cited under the state food and agricultural code for permitting his dogs to roam on property with livestock. Authorities said he would probably have to pay restitution for the dead llamas.

In a rambling interview, Bier argued both that his dog is too sweet and gentle to behave so viciously, and that a human can't be held liable for the thoughts and actions of a dog.

He also said both dogs had lived peaceably with the chickens, ducks and rabbits on his own land, and said the only blood on Cocoa's body when he retrieved him for burial was due to gunshot wounds to his head and stomach — proof he didn't tear apart a llama.

The dog's execution "killed me," Bier said. "I cried for days. I still ain't right … That was my dog, that was my baby. That was my son."

Bier lives across Robinson Creek Road from Janet and Tom Williams, who owned the llamas and a variety of other creatures and exotic birds on what they call the Solitaire Ranch.

Janet Williams was asleep when she heard the llamas screaming and, going outside with a flashlight to investigate, found herself amid carnage she can't shake off.

One llama already was dead and a second was mortally wounded, with the two dogs gripping onto it despite her efforts to scare them off, her husband said.

She's still traumatized, he said Tuesday. "She just can't close her eyes without seeing the face of her favorite little llama," he said.

Bier said he has nothing against the Williamses and wishes he could go over and extend sympathies, except one of the deputies told him not to make contact with Janet Williams.

But he said the Williamses could have helped the situation by keeping the gate to their property closed.

"It's my mistake for letting my dogs off (the chain), your mistake for leaving your gate open," he said. "It's an even field when it comes to who's to blame."